#define  _CRT_SECURE_NO_WARNINGS  1
#include <stdio.h>
int main()
{
	int a, b, c;
	while (scanf("%d %d %d", &a, &b, &c) != EOF)
	{
		if (((a + b > c) + (a + c > b) + (b + c > a)) == 3)
		{
			if (((a == b) + (a == c) + (b == c)) == 3)
			{
				printf("Equilateral triangle!\n");
			}
			else if (((a == b) + (a == c) + (b == c)) == 1)
				printf("Isosceles triangle!\n");
			else
				printf("Ordinary triangle!\n");
		}
		else
			printf("Not a triangle!\n");
	}

	return 0;
}